Everyone has a favorite decade, and for Climate deniers, that decade has got to be, the 70s.
Yes, the decade of disco, kung fu, and watergate
Because in the 70's, Deniers will tell you, All climate scientists believed an ice age was coming. Those crazy climate scientists! Why can't they make up their minds?
But is that really true?
Maybe a little historical perspective is in order.
The first calculations relating CO2 emissions to climate change were done by Svante Arrhenius in the early 20th century. His ideas received some attention, but were largely set aside for many decades.
The international geophysical year of 1957-58 was the first time that modern technology was brought to bear across the planet to study the earth's climatic envelope, and Arrhenius theory seemed to be confirmed.
Long before BIll Nye the science guy, millions got a glimpse of the world of science thru the Bell Telephone hour science series, which featured an avuncular Dr Science, the authority on everything - Dr Frank Baxter. This episode was directed by the great Frank Capra, and shows how climate change had already become mainstream science in 1958.
With the advent of sputnik and the cold war, the importance of a presidential scientific advisory panel became clear. President Johnson's Science Advisory Committee in 1965 produced a groundbreaking study on natural beauty and the environment, which contained a clear warning about climate and CO2.
“Man is unwittingly conducting a vast geophysical experiment....”, noting that emissions by the year 2000 could be enough to cause “measurable and perhaps marked” climate change.
In a special message to congress of February 8, 1965, President Johnson wrote,
"...this generation has altered the composition of the atmosphere on a global scale through radioactive materials and a steady increase in carbon dioxide
from fossil fuels"
But a few scientists were looking at global temperature data, and beginning to worry about another pollution problem. Global Temperatures had been flat or decreasing since the 1940s. Could man's addition of smoke and particulate matter to the atmosphere be blocking out the sun - and leading to a potentially catastrophic global cooling?
One of them was climatologist Stephen Schneider, who talked about that era
recently in a BBC interview.
News of the scientist's concerns made its way into the popular media, such as this 1975 Newsweek article.
The article quoted a number of scientists, and in addition, a National Academy of Science study pointing out that a change in climate would have impacts on global food supply. The Academy was also quoted saying that, in regard to climate change, "in many cases we do not yet know enough to pose the key questions."
Since the National Academy is a good bellweather of where science was at that moment, I decided to read what the original study actually said. This particular study is a model of ambiguity.
"..we do not have a good quantitative understanding of our climate machine
......
Without the fundamental understanding, it does not seem
possible to predict climate.."
The report concludes by saying, "“The onset of (cooling) ..could be several
thousand years in the future, although there is a finite possibility that a
serious worldwide cooling could befall the earth within the next 100 years."
and a few paragraphs later,
“A leading... effect is the enrichment
of the atmospheric CO2 content by the combustion of fossil fuels,
... Such effects may combine .... to offset a future natural cooling trend, or to
enhance a natural warming.”
It was an uncharacteristically muddled effort by the academy, and its conclusions were somewhat distorted in media accounts.
In early 1977, the Global 2000 report to President Jimmy Carter, was clear and explicit about climate .
“Rising CO2 concentrations are of concern because of their potential for
causing a warming of the earth.
...
Agriculture and other human endeavors would have a great difficulty in adapting to
such large, rapid changes in climate.”
I n 1979, the Academy took another crack at the issue, surveying the balance of all the scientific literature of the 70s, and reported:
"If Carbon dioxide continues to increase," there is "no
reason to doubt that climate changes will result, and no reason to
believe that these changes will be negligible....
Ominously warning,
A “wait and see policy
may mean waiting until
it is too late..”
By the mid seventies, a couple of things had happened to clarify our situation.
Number one, global temperatures began a sustained rise that matched the predictions of CO2 effects.
Number two.
the publication of a seminal study marked the beginning of the contemporary view of climate change, and the cycle of ice age glaciations.
The study confirmed a decades old theory, and gave us an understanding as to how the long slow changes in earth's rotation and orbit have been the timing clock of the glaciers.
We'll be talking more about these long term cycles in upcoming programs. But with this study, the stage was set for our current generation of scientists to gain a
whole new understanding of where we are in climatic cycles, and what to
expect in the future.
But, Climate deniers still point to the popular media as evidence of what climate scientists were thinking at the time.
But of course, the gold standard in science is not pop culture, but the peer reviewed study published in a reputable journal.
Most climate Deniers, bless their hearts, don't know the difference.
But real scientists do.
But if there was still any question of what the majority of climate scientists thought in the 1970s, In 2008, a study published in the Bulletin of the American Meteorological Society finally put that question to rest.
In a survey of 71 peer reviewed studies from 1965 to 1979,
7 predicted cooling
20 were neutral
and 44 predicted Global
Warming
The study concluded that "global cooling was never more than a minor aspect of the scientific literature of the era, let alone a consensus" comparable to the agreement of every established scientific organization on the planet that exists today, that climate change is real, we're doing it, the consequences are dire, and we need to stop.
Thanks again for all your comments on this series. Keep them coming, keep telling your friends, and come back again soon for another Climate Denial Crock of the Week.